Lower Eyelid Blepharoplasty 23 Roger L
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Lower Eyelid Blepharoplasty 23 Roger L. Crumley, Behrooz A. Torkian, and Amir M. Karam Anatomical Considerations the orbicularis oculi muscle and (2) an inner lamella, which includes tarsus and conjunctiva. The skin of the lower 2 In no other area of facial aesthetic surgery is such a fragile eyelid, which measures less than 1 mm in thickness, balance struck between form and function as that in eye- retains a smooth delicate texture until it extends beyond lid modification. Owing to the delicate nature of eyelid the lateral orbital rim, where it gradually becomes thicker structural composition and the vital role the eyelids serve and coarser. The eyelid skin, which is essentially devoid of in protecting the visual system, iatrogenic alterations in a subcutaneous fat layer, is interconnected to the under- eyelid anatomy must be made with care, precision, and lying musculus orbicularis oculi by fine connective tissue thoughtful consideration of existing soft tissue structures. attachments in the skin’s pretarsal and preseptal zones. A brief anatomical review is necessary to highlight some of these salient points. With the eyes in primary position, the lower lid should Musculature be well apposed to the globe, with its lid margin roughly The orbicularis oculi muscle can be divided into a darker tangent to the inferior limbus and the orientation of its re- and thicker orbital portion (voluntary) and a thinner and spective palpebral fissure slanted slightly obliquely upward lighter palpebral portion (voluntary and involuntary). The from medial to lateral (occidental norm). An inferior palpe- palpebral portion can be further subdivided into preseptal bral sulcus (lower eyelid crease) is usually identified ϳ5 to and pretarsal components (Fig. 23.2). The larger super- 6 mm from the ciliary margin and roughly delineates the ficial heads of the pretarsal orbicularis unite to form the inferior edge of the tarsal plate and the transition zone from medial canthal tendon, which inserts onto the anterior pretarsal to preseptal orbicularis oculi1 (Fig. 23.1). lacrimal crest, whereas the deep heads unite to insert at the posterior lacrimal crest. Laterally, the fibers condense Lamellae and become firmly attached at the orbital tubercle of 3 The eyelids have been considered as being composed of Whitnall, becoming the lateral canthal tendon. Although two lamellae: (1) an outer lamella, composed of skin and the preseptal orbicularis has fixed attachments with the medial and lateral canthal tendons, the orbital portion does not and instead inserts subcutaneously in the lateral orbital region (contributing to crow’s feet), overlies some of the elevator muscles of the upper lip and ala, and pos- sesses attachments to the infraorbital bony margin. Immediately beneath the submuscular fascia, extend- ing along the posterior surface of the preseptal orbicu- laris, lies the orbital septum. Delineating the boundary between anterior eyelid (outer lamella) and intraorbital contents, it originates at the arcus marginalis along the orbital rim (continuous with orbital periosteum), and after fusing with the capsulopalpebral fascia posteriorly ϳ5 mm below the lower tarsal edge, it forms a single fascial layer that inserts near the tarsal base. The capsulopalpebral head of the inferior rectus is a dense, fibrous, connective tissue expansion, which by virtue of its ultimate attachments to the tarsal plate allows for lower lid retraction during downward gaze. During its forward extension, it encompasses the musculus obliquus inferior, and after reuniting anteriorly, it contributes to the formation of Lockwood’s suspensory ligament (inferior transverse liga- Fig. 23.1 Topographic anatomy of the eyelid, demonstrating natural ment, at which point it is termed the capsulopalpebral fascia, folds. (From Kohn R. Textbook of Ophthalmic Plastic and Reconstructive 4 Surgery. Philadelphia: Lea & Febiger; 1988. Reprinted by permission.) CPF). Although the majority of its fibers terminate near the 271 272 II Aesthetic Facial Surgery Fig. 23.2 Major divisions of the m. orbicularis oculi into pretarsal, preseptal, and orbital com- ponents. inferior tarsal border, some extend through orbital fat con- differences from its other counterparts, including a lighter tributing to compartmentalization, some penetrate the pre- color, a more fibrous and compact lobular pattern, and a septal orbicularis to insert subcutaneously about the lower frequent association with a sizable blood vessel near its eyelid crease, and others extend from the inferior fornix su- medial aspect. The orbital fat can be considered an ady- periorly to contribute to Tenon’s capsule (Fig. 23.3). namic structure because its volume is not related to body habitus, and once removed it is not thought to regenerate. Orbital Fat Innervation Contained behind the orbital septum and within the orbital cavity, the orbital fat has been classically segmented Sensory innervation to the lower lid derives mainly from into discrete pockets (lateral, central, and medial), although the infraorbital nerve with minor contributions from the interconnections truly exist.5 The lateral fat pad is smaller infratrochlear and zygomaticofacial nerve branches. The and more superiorly situated, and the larger nasal pad is blood supply is obtained from the angular, infraorbital, divided by the inferior oblique muscle into a larger central and transverse facial arteries. Situated 2 mm below the fat compartment and an intermediate medial compartment. ciliary margin, between the orbicularis oculi and the tar- (During surgery, care must be taken to avoid injury to sus, is the marginal arcade, which should be avoided if a the inferior oblique.) The medial pad has characteristic subciliary incision is used. Fig. 23.3 Cross-sectional diagram of the lower eyelid demonstrating connective tissue expansion of inferior rectus into its terminal insertions. 23 Lower Eyelid Blepharoplasty 273 Terminology tearing, a burning or gritty sensation, ocular discomfort, foreign bodies, mucus production, eyelid crusting, and Several descriptive terms are used pervasively in the lit- a frequent need to blink are all symptoms suggestive of erature of eyelid analysis and should be understood by borderline or inadequate tear production. A possible those involved in surgical management of this area. atopic cause has to be ruled out. Blepharochalasis is a commonly misused term. It is an Certain systemic diseases, particularly the collagen uncommon disorder of the upper eyelids, of unknown vascular diseases (i.e., systemic lupus erythematosus, cause, which affects mainly young and middle-aged scleroderma, periarteritis nodosa), Sjögren syndrome, females. Blepharochalasis is characterized by recurrent Wegener granulomatosis, ocular pemphigoid, and Stevens– attacks of painless unilateral or bilateral lid edema, caus- Johnson syndrome, can interfere with the glandular lubri- 6,7 ing a loss of skin elasticity and atrophic changes. cating function and should be identified. The infiltrative Dermatochalasis is an acquired condition of increased, ophthalmopathy of Graves’ disease can result in vertical abnormal laxity of the eyelid skin interrelated with eyelid retraction and inadequate corneal protection after genetic predisposition, natural aging phenomenon, and surgery and should be managed with medical treatment environmental influences. It is frequently associated with preoperatively and surgical conservatism during surgery. prolapsed orbital fat. Thyroid hypofunction associated with a myxedematous Steatoblepharon is a condition of true herniation or state may mimic the baggy eyelids of dermatochalasis pseudoherniation of orbital fat behind a weakened orbital and should be ruled out. Incomplete recovery of a previ- septum, causing areas of discrete or diffuse fullness in the ous facial nerve insult may interfere with eyelid closure eyelids. This condition and dermatochalasis are the two and predispose a patient to dry eye syndrome. most common reasons why a patient presents to discuss eyelid surgery. Festoons are single or multiple folds of orbicularis oculi Risk Factors for Postoperative Blindness in the lower lid that drape over onto themselves, creating an external, hammock-like bag. Depending on location, Postoperative blindness, the most catastrophic compli- this bag may be preseptal, orbital, or jugal (cheek). It may cation of blepharoplasty, is associated with retrobulbar 8,9 contain fat. hemorrhage. Factors that influence bleeding tenden- Malar bags are areas of soft tissue fullness on the lat- cies should therefore be identified and controlled before 10 eral edge of the infraorbital ridge and zygomatic promi- surgery. Ingestion of aspirin, nonsteroidal antiinflam- nence just superior to the palpebromalar sulcus. They matory drugs (NSAIDS), antiarthritics, cortisone prepa- are believed to be a result of recurrent dependent tissue rations, and vitamin E should be withheld for at least edema and secondary fibrosis. 14 days before surgery because of qualitative effects on platelet function. Over-the-counter medications should be discontinued as well because gingko biloba, for exam- Preoperative Evaluation ple, has been implicated in excessive bleeding. Similarly, St. John’s wort is known to have hypertensive effects A systematic and thorough preoperative assessment of through a monoamine oxidase inhibitor mechanism. blepharoplasty candidates is essential to minimize poten- Warfarin compounds, if medically feasible, should be tial postoperative complications. Thus,